Strategic Pole Assignment Based on Gain Ratio Heuristic for Vibration Control of Magnetic Levitation System

An accurate evaluation of controller parameters governed by the appropriate placement of poles and zeroes is necessary to suppress vibrations in any system. Stringent force equilibrium balance conditions must be satisfied to obtain the successful and sustained magnetic levitation of an object with low vibrations, otherwise it would either fall down, slide sideways, or be pulled up. Despite applying sufficient damping, vibrations are observed, due to which a properly tuned active control action is required.

This paper proposes and analyses a heuristic approach based on the gain ratio of the actual and the desired transfer function for tuning a PID controller by assigning the pole at an appropriate location based on the degree balance concept of the Diophantine equation and pole placement technique.

The application of the proposed strategy results in the saving of computational time in the hit and trials of successive pole assignments, elimination of an infeasible search domain, and provision of a heuristic guidance in locating an acceptable region of the pole assignment.

Simulation and real-time responses, root locus, pole-zero, and robustness analysis have been done to establish the validity of the new pole assignment.